| 摘要 |
There is disclosed a mechanical transducer which is particularly adapted for use as an actuator for a damper in a ventilating system. The transducer comprises a housing having a motor drive unit with a rotary shaft output therefrom carried on one wall of the housing and in driving connection to a lead screw which is rotatably carried by thrust bearing means on the wall of said housing. A traveling nut member is engaged on the lead screw and a tubular work output member extends through an opposite wall of the housing in generally co-axial alignment with the lead screw. The inboard end of the tubular member is secured to the traveling nut member whereby the lead screw it totally enclosed. The outboard end of the tubular member bears a work-receiving means which, preferably, is a tapped plug for removable attachment to an actuating lever of the damper unit. The housing also contains the electronic controls for the motor drive unit, including an electrical feedback circuit having a variable, passive electrical component such as a variable resistor with a slider mounted thereon which is mechanically connected to the traveling nut member. In its preferred embodiment, the circuit board is positioned in the housing above the lead screw and the slider bears downwardly projecting arm means mechanically linked to the traveling nut member. This construction greatly facilitates the installation and service of the device since the circuit board and associated slider can simply be lifted out of and returned into engagement with the traveling nut member through the upper, open end of the housing which is covered with a removable cover member.
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